ab8500_charger: Adds support for legacy USB chargers

A Legacy USB charger should be handled directly by the charger
driver.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Marcus Cooper <marcus.xm.cooper@stericsson.com>
Reviewed-by: Karl KOMIEROWSKI <karl.komierowski@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

diff --git a/drivers/power/ab8500_charger.c b/drivers/power/ab8500_charger.c
index 6ba7eff..d5a8bda 100644 (file)
--- a/drivers/power/ab8500_charger.c
+++ b/drivers/power/ab8500_charger.c
@@ -88,6 +88,9 @@
 /* Step up/down delay in us */
 #define STEP_UDELAY                    1000
 
+/* Wait for enumeration before charging in ms */
+#define WAIT_FOR_USB_ENUMERATION       5 * 1000
+
 #define CHARGER_STATUS_POLL 10 /* in ms */
 
 /* UsbLineStatus register - usb types */
@@ -201,6 +204,7 @@ struct ab8500_charger_usb_state {
  *                     charger is enabled
  * @vbat               Battery voltage
  * @old_vbat           Previously measured battery voltage
+ * @usb_device_is_unrecognised USB device is unrecognised by the hardware
  * @autopower          Indicate if we should have automatic pwron after pwrloss
  * @autopower_cfg      platform specific power config support for "pwron after pwrloss"
  * @parent:            Pointer to the struct ab8500
@@ -219,6 +223,7 @@ struct ab8500_charger_usb_state {
  * @check_usbchgnotok_work:    Work for checking USB charger not ok status
  * @kick_wd_work:              Work for kicking the charger watchdog in case
  *                             of ABB rev 1.* due to the watchog logic bug
+ * @attach_work:               Work for checking the usb enumeration
  * @ac_charger_attached_work:  Work for checking if AC charger is still
  *                             connected
  * @usb_charger_attached_work: Work for checking if USB charger is still
@@ -243,6 +248,7 @@ struct ab8500_charger {
        bool vddadc_en_usb;
        int vbat;
        int old_vbat;
+       bool usb_device_is_unrecognised;
        bool autopower;
        bool autopower_cfg;
        struct ab8500 *parent;
@@ -260,6 +266,7 @@ struct ab8500_charger {
        struct delayed_work check_hw_failure_work;
        struct delayed_work check_usbchgnotok_work;
        struct delayed_work kick_wd_work;
+       struct delayed_work attach_work;
        struct delayed_work ac_charger_attached_work;
        struct delayed_work usb_charger_attached_work;
        struct work_struct ac_work;
@@ -597,6 +604,8 @@ static int ab8500_charger_max_usb_curr(struct ab8500_charger *di,
 {
        int ret = 0;
 
+       di->usb_device_is_unrecognised = false;
+
        switch (link_status) {
        case USB_STAT_STD_HOST_NC:
        case USB_STAT_STD_HOST_C_NS:
@@ -642,9 +651,15 @@ static int ab8500_charger_max_usb_curr(struct ab8500_charger *di,
                dev_dbg(di->dev, "USB Type - 0x%02x MaxCurr: %d", link_status,
                                di->max_usb_in_curr);
                break;
+       case USB_STAT_NOT_CONFIGURED:
+               if (di->vbus_detected) {
+                       di->usb_device_is_unrecognised = true;
+                       dev_dbg(di->dev, "USB Type - Legacy charger.\n");
+                       di->max_usb_in_curr = USB_CH_IP_CUR_LVL_1P5;
+                       break;
+               }
        case USB_STAT_HM_IDGND:
        case USB_STAT_NOT_VALID_LINK:
-       case USB_STAT_NOT_CONFIGURED:
                dev_err(di->dev, "USB Type - Charging not allowed\n");
                di->max_usb_in_curr = USB_CH_IP_CUR_LVL_0P05;
                ret = -ENXIO;
@@ -1912,6 +1927,29 @@ static void ab8500_charger_detect_usb_type_work(struct work_struct *work)
 }
 
 /**
+ * ab8500_charger_usb_link_attach_work() - delayd work to detect USB type
+ * @work:      pointer to the work_struct structure
+ *
+ * Detect the type of USB plugged
+ */
+static void ab8500_charger_usb_link_attach_work(struct work_struct *work)
+{
+       struct ab8500_charger *di =
+               container_of(work, struct ab8500_charger, attach_work.work);
+       int ret;
+
+       /* Update maximum input current if USB enumeration is not detected */
+       if (!di->usb.charger_online) {
+               ret = ab8500_charger_set_vbus_in_curr(di, di->max_usb_in_curr);
+               if (ret)
+                       return;
+       }
+
+       ab8500_charger_set_usb_connected(di, true);
+       ab8500_power_supply_changed(di, &di->usb_chg.psy);
+}
+
+/**
  * ab8500_charger_usb_link_status_work() - work to detect USB type
  * @work:      pointer to the work_struct structure
  *
@@ -1937,23 +1975,29 @@ static void ab8500_charger_usb_link_status_work(struct work_struct *work)
                di->vbus_detected = 0;
                ab8500_charger_set_usb_connected(di, false);
                ab8500_power_supply_changed(di, &di->usb_chg.psy);
-       } else {
-               di->vbus_detected = 1;
-               ret = ab8500_charger_read_usb_type(di);
-               if (!ret) {
-                       /* Update maximum input current */
-                       ret = ab8500_charger_set_vbus_in_curr(di,
-                                       di->max_usb_in_curr);
-                       if (ret)
-                               return;
+               return;
+       }
 
-                       ab8500_charger_set_usb_connected(di, true);
-                       ab8500_power_supply_changed(di, &di->usb_chg.psy);
-               } else if (ret == -ENXIO) {
-                       /* No valid charger type detected */
-                       ab8500_charger_set_usb_connected(di, false);
-                       ab8500_power_supply_changed(di, &di->usb_chg.psy);
+       di->vbus_detected = 1;
+       ret = ab8500_charger_read_usb_type(di);
+       if (!ret) {
+               if (di->usb_device_is_unrecognised) {
+                       dev_dbg(di->dev,
+                               "Potential Legacy Charger device. "
+                               "Delay work for %d msec for USB enum "
+                               "to finish",
+                               WAIT_FOR_USB_ENUMERATION);
+                       queue_delayed_work(di->charger_wq,
+                                          &di->attach_work,
+                                          msecs_to_jiffies(WAIT_FOR_USB_ENUMERATION));
+               } else {
+                       queue_delayed_work(di->charger_wq,
+                                          &di->attach_work, 0);
                }
+       } else if (ret == -ENXIO) {
+               /* No valid charger type detected */
+               ab8500_charger_set_usb_connected(di, false);
+               ab8500_power_supply_changed(di, &di->usb_chg.psy);
        }
 }
 
@@ -2911,6 +2955,9 @@ static int ab8500_charger_probe(struct platform_device *pdev)
        INIT_DEFERRABLE_WORK(&di->check_vbat_work,
                ab8500_charger_check_vbat_work);
 
+       INIT_DELAYED_WORK(&di->attach_work,
+               ab8500_charger_usb_link_attach_work);
+
        /* Init work for charger detection */
        INIT_WORK(&di->usb_link_status_work,
                ab8500_charger_usb_link_status_work);